Muhammed Fuad Rashid Petroleum Engineering Department at Koya University Mechanics of material Laboratory 2020

1. Faculty of Engineering Petroleum
Engineering Department
Mechanics of Material Laboratory, 2nd stage
Experiment Name: Compressive strength test
Prepared by: Muhammed Fuad Rashid
Ahmad Jalal Hassan
Muhammad Hassan Aziz
Safwan Tofiq Ameen
Group: A
Supervised by: Dr.Diyar

2. 2
Contents
1.0. Introduction.....................................................................................................................3
2.0. Aim of the test.................................................................................................................4
3.0. Methodology...................................................................................................................5
3.1.The compressive Test Process............................................................................................5
3.2.Sample preparation...........................................................................................................6
3.3.Test machine.....................................................................................................................7
4.0. Test proceeding...............................................................................................................8
5.0. Results and discussion .....................................................................................................9
5.1. Results obtained from the graph(data) ...........................................................................11
6.0. Conclusion..........................................................................................................................12
7.0. Reference......................................................................................................................12

3. 3
1.0. Introduction
Compressive strength test, mechanical test measuring the maximum amount of
compressive load a material can bear before fracturing. The test piece, usually in the
form of a cube, prism, or cylinder, is compressed between the platens of a
compression-testing machine by a gradually applied load.
Brittle materials such as rock, brick, cast iron, and concrete may exhibit great
compressive strengths; but ultimately they fracture. The crushing strength of
concrete, determined by breaking a cube, and often called the cube strength, reaches
values of about 3 tons per square inch, that of granite 10 tons per square inch, and
that of cast iron from 25 to 60 tons per square inch.
Some ductile metals, such as mild steel, have very great compressive strengths; but
the actual values are difficult to measure. When a load is applied to a ductile metal,
it deforms elastically up to a certain point, and then plastic deformation occurs.
Increasing loads may even completely flatten a test piece without any definite
fracture occurring, so that no value can be obtained for the compressive strength.
The custom of quoting tensile-strength values in these cases is inaccurate but safe,
compressive strength being always greater.

4. 4
2.0. Aim of the test
The goal of a compression test is to determine the behavior or response of a material
while it experiences a compressive load by measuring fundamental variables, such
as, strain, stress, and deformation. By testing a material in compression the
compressive strength, yield strength, ultimate strength, elastic limit, and the elastic
modulus among other parameters may all be determined. With the understanding of
these different parameters and the values associated with a specific material it may
be determined whether or not the material is suited for specific applications or if it
will fail under the specified stresses.

5. 5
3.0. Methodology
3.1.The compressive Test Process
The evaluation of the mechanical behavior of a sample under conditions of
compression test can be performed to provide basic material property data that is
critical for component design and service performance assessment. The requirements
for compression strength values and the methods for testing these properties are
specified in various standards for a wide variety of materials. Testing can be
performed on machined material samples or on full-size or scale models of actual
components. These tests are typically performed using a universal mechanical
testing instrument.
A compression test is a method for determining the behavior of materials under a
compressive load. Compression tests are conducted by loading the test specimen
between two plates, and then applying a force to the specimen by moving the
crossheads together. During the test, the specimen is compressed, and deformation
versus the applied load is recorded. The compression test is used to determine elastic
limit, proportional limit, yield point, yield strength, and (for some materials)
compressive strength.

6. 6
3.2.Sample preparation
To perform a tension or compression test a specimen of the material is
made into a “standard” shape and , . l,The sample preparation of a compressive
test is just like a tensile test but it differs from the tensile test from some things for
example in compressive test we don’t have the gage-lengh of the sample because
we compressive the whole sample not just apart of the sample and again we also
measure the cross-sectional area of the sample that means we measure the length
and width and thickness of the specimen, our specimen was a both side cross
sectional of rectangular shape. And the specimen’s composition was(wood) ant its
dimension’s is right below, so finally The sample was already machined to the
proper dimensions required for the test, according to ASTM standards
Thickness= 19.8mm
Width= 18.9mm
Length= 372mm

7. 7
3.3.Test machine
A machine is used in compressive test experiments to perform the experiment and
our labs machine for compressive test have the specifications and its description
below;
Model No. 5982
System ID /SN 5982L33117
Configuration E1-F1-G1
capacity 100KN(2500Ib)
weight 784kg(1732Ib)
Date of manufacture March,21,2012
voltage 220 Volts
frequency 47-63 Hz
Maximum power 3500 VA
Circuit breaker 20Amp
Short circuit current

8. 8
4.0. Test proceeding
First after the specimen was prepared which its mentioned how prepared in
preparation of sample section, now the first should be done The Blue Hill data
acquisition software was started and The load cell was zeroed to ensure that the
software only measured the measured the compressive load applied to the
specimen or we can delay this option till the start of compressive test axial load
procedure, after that we sat our specimen on the flat steel siting place right in the
center of circle of the place which is labeled as 3 circles so as to obtain the right
values and properties of the sample, also prevent damage to the machine.
After the sample was connected to the machine the blue hill software was set to the
right options for the specimen’s property and proceeding the software to prepare for
the test but there’s some need to be mentioned for example, the stress ratio (defined
at definition section) ;
Stress ratio=1.5mm/minute
And its very important to set the strain ration in a small ratio to ensure the accurate
results and not directly rapture the specimen .then our curve will not give the whole
details about the test.
Then, the test was started, and the specimen was load P Applied from a stress ratio
of 1.5 as metioned, resulting in a measureable compressive stress, after that the load
was applied we waited nearly for 6 minutes and till the sample was fractured and
got to rapture ,what we observed meanwhile was the sample was going to bending
postion and the sample got to bend(like curve) after a moments later ,as the axial
load increases on the sample finally the sample at a specific load got to fracture , and
that was the final steps of proceeding the experiment.

9. 9
5.0. Results and discussion
After the test was produced ,the data was gathered and obtained the right values on
a graph(software’s proceeding) ,from the graph we can determine lot of the
specimens properties which is the aim of our experiment
according to the fig.1 which obtained from the test ,we will try to explain the
following terms ;
 Proportional limit
 Elastic limit
 Ultimate stress
 Fracture or rapture
1.proportional limit First a our specimen have Proportional limit which can be
difined as From the 0 point to the point called proportional limit which the
stress strain curve is a straight line according to hooks law as long as stress applied
-5
0
5
10
15
20
0 0.002 0.004 0.006 0.008 0.01 0.012
compressivestress(MPa)
compressive strain(mm)

10. 10
the sample strains and elongate , here in our diagram the proportional limit is
relatively when our force (N) equals=6,497.12N
2.elastic limit can be defined as the limit after that limit the sample will no more
back to original shape, our samples elastic limit can nearly determined between
range of Force of (5,229.85)N
3.Ultimate stress can be defined easily as the top of our curve in the diagram which
is the ,maximum stress could the specimen take which can also be determined nearly
18.182MPa
4.bending can be defined as the position of the specimen when the axial is Appling
at a point the specimen will be observed as a curve shape not straight line
Figure 1example of instron machine proceeding compressive test on a circular shape specimen(our was rectangular)

11. 11
5.1. Results obtained from the graph(data)
1.youngs modulus=
Young modulus=ratio stress/ratio strain=(y2-y1)(x2-x1)
Youngs modulus Test 1 =5.86𝐺𝑃𝑎
Youngs modulus Test 2=7.3𝐺𝑃𝑎
Youngs modulus test 3=7.05𝐺𝑃𝑎
Young modulus average=6.7𝐺𝑃𝑎
2.maximum stress 𝜎 = 18.18𝐺𝑃𝑎
3.maximum elongation 𝛿 = 3.644𝑚𝑚
4.maximum load 𝜌 = 6947.14𝑁

12. 12
6.0. Conclusion
The aim of the test is achieved and the test was proceded successfully , the data
about the material was curefully obtained which was a specimen of (wood) also
performing thus experiments is very important because for example Compression
test is important in industry. This is because in manufacturing industry, suitable
material should be used to build certain objects that meet the mechanical properties
of the material. Compression test is useful to determine the compressive strength,
yield strength, ultimate strength, elastic limit, and the elastic modulus. With the
understanding of these different parameters and values associated with a specific
material it may be determined the material used is suited for specific applications or
if it will fail under the test.
7.0. Reference
1. Instron.us. (2019). What is Compression Testing? - Instron. [online] Available
at: https://www.instron.us/en-us/our-company/library/test-types/compression-
test [Accessed 9 Nov. 2019].
2. UniProjects, R. (2019). Comparison Of The Strength Of Concrete Produced
With Coarse Aggregate In Different Location | Project Materials |
UniProjects.Net. [online] Google.com. Available at:
https://www.google.com/url?client=internal-element-
cse&cx=002312555289270087503:b-
_um9mrm8g&q=https://uniprojects.net/project-materials/comparison-of-the-
strength-of-concrete-produced-with-coarse-aggregate-in-different-
location&sa=U&ved=2ahUKEwjFpu2p-
N3lAhXP_aQKHfNhAJkQFjAAegQIABAB&usg=AOvVaw1ScYIkfPcdzOy
Ll8LfQVpy [Accessed 9 Nov. 2019].
3. Belyayev, N. (2019). Problems in Strength of Materials by N. M. Belyayev -
Book - Read Online. [online] Scribd. Available at:
https://www.scribd.com/book/282578717/Problems-in-Strength-of-Materials
[Accessed 9 Nov. 2019].